Exceptional and rare prolonged levels of heat developed over New York and western New England on this day as a super heated air mass, which had been sitting over the midwest and upper Mississippi valley for several days prior, moved into the Northeast (850 mb temperatures climbed from +20° C at 8am to +23° C, measured at 8pm). The temperature at Albany climbed to 91° and heat index to 100° at noon. The temperature and heat index then remained above 90° and 100° respectively for an incredible ten consecutive hours through 9pm.

This super heated air mass, in combination with a moderately strong southwesterly boundary layer flow of 15-35 mph through the bottom couple of thousand feet in the atmosphere created a highly favorable downslope wind scenario into especially the Capital Region and Hudson valley which caused the air to heat further as it descended along the eastern slopes of the higher terrain of the Catskills, compressing and thus warming it further. The result was the highest temperatures in the Capital Region in sixteen years with Albany's high reaching 99°, a temperature not seen since July 14, 1995, the day prior to the super derecho which ravaged the entire region with widespread damaging wind. The downslope compressional warming process is also a drying process which typically means the dewpoints go down by a good margin. In this case, however, the dewpoints only dropped by a couple of degrees, remaining above 70° all day creating a prolonged period of absolutely oppressive heat conditions with a peak heat index at Albany of 110° at 6pm. Despite the high heat and humidity, no record high was achieved with the record for this date remaining 101° set in 1930. The morning low temperature of 76° @ Albany, however, did set a record "High" minimum, breaking the prior record of 74° set in 1926

A strongly capped atmosphere (very warm air aloft) prevented any significant thunderstorms from forming. Only a few isolated brief showers/thunder showers occurred during the late afternoon and early evening, otherwise the day was generally dry. So despite conditions in the atmosphere being similar to those of July 14, 1995, no severe weather occurred due to a stronger cap and lack of any upstream trigger mechanism to produce thunderstorms.

Albany's Heat Trace

Time

Temperature

Dewpoint

Heat Index

Wind

Noon

91°

73°

100°

South 13 mph

1pm

94°

74°

105°

South 14 mph

2pm

96°

70°

104°

SW 12 mph

3pm

97°

71°

106°

SSW 10 mph

4pm

98°

72°

109°

SW 12 mph

5pm

99°

71°

109°

SW 14 mph

6pm

98°

73°

110°

WSW 7 mph

7pm

96°

73°

107°

SW 8 mph

8pm

93°

73°

103°

SW 7 mph

9pm

91°

73°

100°

SW 7 mph

10pm

88°

74°

97°

South 5 mph

11pm

86°

74°

94°

South 5 mph

Regional Heat Numbers: WeatherNet 6 and Local ASOS Reports

Town

County

High Temperature

North Adams, MA

Berkshire

95° - Peak Heat Index: 101°

Pittsfield, MA

Berkshire

93° - Peak Heat Index: 97°

Alford, MA

Berkshire

95°

Colonie

Albany

99° - Peak Heat Index: 107°

Pine Bush

Albany

100°

Newtonville

Albany

98°

Feura Bush

Albany

99°

Glenmont

Albany

97°

Cohoes

Albany

98°

Medusa

Albany

95°

Landgrove, VT

Bennington

88°

Bennington, VT

Bennington

94° - Peak Heat Index: 101°

North Chatham

Columbia

97°

Ancramdale

Columbia

93°

Livingston

Columbia

98°

Taghkanic

Columbia

96°

Hudson

Columbia

101°

Red Hook

Dutchess

100°

Poughkeepsie

Dutchess

98° - Peak Heat Index: 105°

Broadalbin

Fulton

96°

Gloversville

Fulton

98°

Catskill

Greene

100°

Round Top

Greene

98°

Halcott

Greene

91°

Hoffmeister

Hamilton

89°

Lake Pleasant

Hamilton

90°

Amsterdam

Montgomery

98°

Palatine Bridge

Montgomery

96°

Fonda

Montgomery

96°

Oneonta

Otsego

96°

East Worcester

Otsego

92°

Schaghticoke

Rensselaer

94°

Danby, VT

Rutland

87°

Moreau

Saratoga

98°

Milton

Saratoga

99° - Peak Heat Index: 112°

Charlton

Saratoga

95°

Saratoga Springs

Saratoga

98°

Duanesburg

Schenectady

95°

Scotia

Schenectady

97°

Middleburgh

Schoharie

95°

Gilboa

Schoharie

90°

Summit

Schoharie

93°

Fulton

Schoharie

98°

Jefferson

Schoharie

95°

Ulster Park

Ulster

98°

Kerhonkson

Ulster

97°

Whiteport

Ulster

101°

West Shokan

Ulster

96°

Phoenicia

Ulster

92°

Saugerties

Ulster

97°

Cossayuna

Washington

93°

Eagle Bridge

Washington

97°

Glens Falls

Warren

96° - Peak Heat Index: 105°

Friday July 22, 2011
Excessive Heat

Significant to excessive heat continued across the region on this day. However, different from Thursday July 21, a considerable break from the oppressive humidity occurred with the passage of a dewpoint front during the morning. Dewpoints fell from the sky high mid 70s in the Capital Region early in the morning into at one point the lower 50s (due to mixing of dry air aloft down to the ground) during the afternoon. The net result was peak heat index values not going above 95° vs 110° heat index values on the 21st. A pleasant breeze, gusting at times to 20-25 mph aided in the more comfortable feel to the air, vs. the air on the 21st where the wind produced blast furnace like conditions at times. Temperatures, however, remained quite hot, with readings ranging from the lower to mid 90s on average except in the mid Hudson valley, including eastern Greene, Columbia, Ulster, Dutchess, and Litchfield counties where high temperatures ranged from 97° to 102° with heat index values up to 110°. The dewpoint front only made it into the mid Hudson valley during the mid to late afternoon which allowed oppressive heat conditions to prevail much of the day with lower sixty degree dewpoints not arriving until the early evening.